Using the Armory client, is it possible to specify one of my existing "receive" addresses in my wallet as a "change" address when I create a spend transactions? (Instead of the Armory client creating a new "change" address)

1 Answer
1

Yes you can, but you have to switch to "Expert" usermode from the main window. After you do, the "Send Bitcoins" window will have an option for customizing the change address. You can click on the addressbook and select any address in any wallet. Or really put in any address you want.

Just remember that you are compromising your privacy by reusing addresses. Even when you don't reuse addresses, there's a surprisingly amount of linkage between your addresses already, just by the way they are combined for some transactions. By reusing change addresses, you are dramatically amplifying that effect. That why this feature is hidden under the "Expert Mode."

For instance, if you always shuffle your coins between 10 addresses, then there is no question that all 10 addresses will eventually be linked, and undeniably part of the same wallet. Thus, every person you ever transact with, will have the capability to see your entire wallet balance at any time, as well as every transaction you ever execute.

I think a preference to use the sending address for change by default would be useful.
– Steven RooseApr 29 '13 at 13:29

4

That's one of the options when you use this feature in "Expert" usermode. You can select the specific address you want to send to, or you can select "Send change to first sending address". There's also a button that says "Remember this for future transactions with this wallet." Combine those two, and sending money will never generate new addresses.
– etotheipiMay 6 '13 at 14:31

Thanks for the detailed answer. I understand the privacy implications.
– armory_userMay 7 '13 at 20:50

It is incorrect to say you're compromising your privacy by reusing addresses. As you mentioned, there is a huge amount of linkage between your addresses. It has been shown that even if you use change addresses, you can still be easily tracked: anonymity-in-bitcoin.blogspot.com/2011/07/… . However, transparently using change addresses makes bitcoins incredibly more difficult to back up correctly, since every time you pay, you have to back up new addresses. This is important, so It would be great if you could change your answer to reflect that.
– B TDec 8 '13 at 23:04

If you are using Armory, the address chain is deterministic. This means that you backup your wallet one time, and all addresses you ever use will be protected by that backup, even if you use millions of addresses. This is why Armory discourages address reuse when using Armory... because you can use a new address everytime without complicating your backups.
– etotheipiApr 16 '14 at 18:37